DHCP Problems

[xari]

Hi guys!

I am new in the community and this is my first post. I have some problems with DHCP and I
need some help. Till now i couldnt find it that is why i decided to try this forum.
Maybe someone out there can help me.

A little background: We develope software and it is sold with the hardware (laptop). Our software is a closed system. The user
cannot change the settings of the computer, and he only has access to what we allow him to see. Our software runs under WINNT(SP6a) and WINXP (SP2). (both english version)
Each system is a client, and it has to connect to our central server. Till now we had static ip addresses, but now we
are changing to dhcp and we have to set the system for dhcp. We distribute our software with a cd and not online.
Setting the system for dhcp is no big deal, I found the registry keys to activate dhcp. No big deal.
But I have some questions and some problems, and till now i was not able to find an answer to them:

1.- When the Windows DHCP client is activated, warnings are displayed if the DHCP Server cannot be reached, for example,
or if the DHCP client could not get a valid address. Is it possible to deactivate these warnings? we deliver our software worldwide and the warning is only in english.

2.- What happens with the network interface card if the lease time expires and the client cannot renew the dhcp address (for example, he is somewhere in the desert)? will windows still recognize the card and will windows
use the last valid address, although the lease time expired? or is it not possible in windows to continue using that network interface?

3.- We deliver an interface with our system. That interface establish a connection to the laptop. We have some
cable interfaces where interface and laptop are linked through a network cable. That means that the same network interface card could be used for two different targets:
a) Establishing the connection to the main server (when connected to our network) Our system gets only in this case
the dhcp configuration. He has to be in our network.
b) Establishing the connection to the interface (TCP-IP Communication too) The interface gets an IP based on the laptop ip address. That is why it is so important that the laptop has an IP configuration.


When we deliver our system we cannot assure that the user will go online with the system and will be able to
get a valid dhcp address. But he must be able to work with the interface, that is to say, he must be able to establish
a connection through the network interface card to the interface. But the laptop has no DHCP configuration and the interface cannot
get an ip address! And i cannot use APIPA for the laptop
because we use WINNT. So I thought: Ok, i will write the DHCP configuration direct in the registry. Kind
of registry hacking.
My idea was to do what APIPA do, but manually. Is that possible? I thought about writting in the registry the needed keys (DHCP
address, DHCP subnet mask, and so on) so that windows will recognize the network interface card and can use it.
Is that possible? Do i have problems with the lease time? Has someone already tried that? I thought it would be enough
if i activate in the registry DHCP and write the DHCP address, DHCP subnet mask in the network interface card, but it doesnt work properly. My idea was to use that manual configuration till he goes online and gets a real configuration from our DHCP server.
If that could be possible our installation software would write in the registry a standard DHCP configuration so that the interface can get an ip address based on that configuration and the user is able to work. The next time he goes online in our network the system will get a valid dhcp configuration from our dhcp server.

4.- What would happen exactly if i had a DHCP Configuration(DHCPIPAddress, and so on) in the registry for a network interface card but at the same time
there is a static IP Address for the same network interface card "IPaddress"? which one will take WINNT? and winxp? I have read
that the static value will overwrite the dinamic configuration. is that true?


In WINXP, i think, there is something like "secondary IP addresses" in case that it is not possible to get a dinamic address. I cannot use this solution because that doesnt work for winnt, if i am not wrong.

The problem is that i have to find a solution which works for WINNT and WINXP. That is why I post the same message in two different forums. I think i give you the most important information
about our system. If I forgot something, just ask. I hope I could picture the problem... it is kind of difficult..

Maybe someone has had a similar problem!

Any help will be appreciated.

Xari.